I would say that labelling or categorizing things (people, places, animals, &c.) is a part of human nature. As fullermdwrote, it's the difference between "description" and "definition." At various times in our lives, we ourselves have different lables that can be applied to us some of which change over time, some stay with us for our entire lives. Some describe our relationships with others while others may describe what we do (and it could even be argued that what we do is still a relationship to other humans). For example when I was a young, I had the labels: Child/Son, Grandchild/son, Nephew, Cousin. As I grew older, I could add: "boyfriend" to the list. Now instead of "boyfriend", it's "fiance." Soon, that will again change to "husband". This doesn't even include specific descriptions like "student" "employee" "hockey player" or labels of age or appearence. I suspect that we humans have been labelling things for purposes of description since Og first picked up a bone and hit an animal over the head and called it dinner instead of animal. Just my 2 cents - interesting conversation though - definite food for thought.